Alkanoyl-alpha-ethylbenzylureas



Patented Sept. 30, 19 52 UNITED STATES PATENT OFFICE ALKANOYL-a-ETHYLBENZYLUREAS Robert Duschinsky, Essex Fells, N. J., assignor to Hoffmann-La Roche Inc., Nutley, N. J a corporation of New Jersey No Drawing. Application July 15, 1950, Serial No. 174,117

3 Claims. 1 This invention relates toa-ethylbenzylureas and to the method for preparing the same. The new compounds can be represented by the following formula:

wherein R is a member of the group consisting of hydrogen and lower aliphatic carboxylic acyl. Compounds of the present invention are useful as anticonvulsants and analgesics.

The simplest member of the new compounds 2 (R in the above formula being H) is -ethylbenzylurea. It can be prepared by reacting a.- ethylbenzylamine in the form of its acid addition salts with an alkali metal cyanate, as for example, sodium cyanate or potassium cyanate, When the optically active forms of a-ethylbenzylamine are employed, the optically active D-aethylbenzylurea and L-a-ethylbenzylurea are obtained. By acylating a-ethylbenzylurea with a lower aliphatic carboxylic acyl halide there are produced the corresponding compounds where R. in the above formula is lower aliphatic car- EXAMPLE 2 D-a-ethylbenzylurea A solution of 31.5 grams of D-a-ethylbenzylamine L-hydrogen malate in 150 cc. of water and 42 cc. of methanol was refluxed for 10 minutes with a solution of 21.3 grams of potassium cyanate in 48 cc. of water. The resultant solution was evaporated on the steam bath to about one-half of its original volume and cooled. D-aethylbenzylurea precipitated. After recrystallization from 250 cc. of benzene, the product had a melting point of 120-121 0.; [l =+50.4.

EXAMPLE 3 L-a-BthZJZbGTLZZ/ZM'll A solution of 17.0 grams of L-a-ethylbenzylamine D-hydrogen tartrate in 75 cc. of water -ing with 1.15 grams of propionyl chloride.

and 21 cc. of methanol was refluxed for 10 minutes with a solution of 10.7 grams of potassium cyanate in 15 cc. ofwater. The resultant solution was evaporated on the steam bath to about one-half its original volume and cooled. After cooling, L-a-ethylbenzylurea precipitated. Upon recrystallization from 150 cc. of benzene, the product melted at 119.5-121 0.; [a] =--50.0.

EXAMPLE 4 I 1- (a-ethylbenzyl) -3-acet1 Zurea A solution of 2 grams of D,L-a-ethylbenzylurea in 11 cc. of pyridine was treatedwhile cooling with 9'70 mg. of acetyl chloride. The resultant mixture was heated on the steam bath for onehalf an hour and then 25 cc. of water and 10 cc. of concentrated hydrochloric acid were added. 1 (a ethylbenzyl) 3 acetylurea precipitated. After recrystallization from a mixture of 8 cc.

-of alcohol and 8 cc. of water, the compound melted at 88-89" C.

' EXAMPLE 5 l-(a-ethylbenzyl) -3-propionylurea A solution of 1.78 grams of D,L-a-ethylbenzylurea in 6 cc. of pyridine was treated while cool- The resultant mixture was refluxed for minutes. After cooling and addition of 20 cc. of water and Sec. of concentrated hydrochloric acid, l-(aethylbenzyl)-3-propionylurea crystallized. After recrystallization from amixture of 20 cc. of alcohol and 30 cc. of water, the compound had a melting point of 98-99 C.

I claim:

1. l-(a-ethylbenzyl) -3-acetylurea.

2. r 1- (a-e'thylbenzyl) -3-propionylurea.

3. 1-(a-ethylbenzyD-3-lower alkanoyl urea.

ROBERT DlJSCHINSKY.

REFERENCES CITED The following references are of record in the file of this patent:

Kann: Ber. deut. chem, vol. 2'7 (1894), p. 2308'.

Brander: Rec. Trav. chim. pays basl, vol. 37 (1918). pp. 82-83.

Jones et al.: "J'. Am. Chem. Soc, vol. 48 (1926), pp. 179-180.

Harris et al.: J. Am. Chem. 800.," vol. 68' 11946). p. 847.

Montague et al.: fC'omptes Rendus Acad. Sci.,"

Vol. 191, (1930), p. 141. 

3. 1-(A-ETHYLBENZYL) -3-LOWER ALKANOYL UREA. 